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| Newer page: | version 3 | Last edited on Thursday, October 21, 2004 5:13:33 pm | by AristotlePagaltzis | |
| Older page: | version 2 | Last edited on Friday, July 19, 2002 11:26:22 pm | by !PerryLorier | Revert |
@@ -1,874 +1 @@
-Authentication Gateway HOWTO
-!!!Authentication Gateway HOWTO
-!Nathan Zorn
-
- zornnh@musc.edu
-
-
-
-__Revision History__Revision .052002-05-10Revised by: nhzRevision .042002-02-28Revised by: nhzRevision .032001-09-28Revised by: nhzRevision .022001-09-28Revised by: KETRevision .012001-09-06Revised by: nhz
-
-
-
-
-
- There are many concerns with the security of wireless networks and
-public access areas such as libraries or dormitories. These
-concerns are not met with current security implementations. A work
-around has been proposed by using an authentication gateway. This
-gateway addresses the security concerns by forcing the user to
-authenticate in order to use the network.
-
-
-
-
-
-
-----; __Table of Contents__; 1. Introduction: ; 1.1. Copyright Information; 1.2. Disclaimer; 1.3. New Versions; 1.4. Credits; 1.5. Feedback; 2. What is needed: ; 2.1. Netfilter; 2.2. Software for dynamic Netfilter rules.; 2.3. DHCP Server; 2.4. Authentication mechanism; 2.5. DNS Server; 3. Setting up the Gateway Services: ; 3.1. Netfilter Setup; 3.2. Dynamic Netfilter rules.; 3.3. DHCP Server Setup; 3.4. Authentication Method Setup; 3.5. DNS Setup; 4. Using the authentication gateway; 5. Concluding Remarks; 6. Additional Resources; 7. Questions and Answers
-!!!1. Introduction
-
- With wireless networks and public acces areas it is very easy for an
-unauthorized user to gain access. Unauthorized users can look for a
-signal and grab connection information from the signal.
-Unauthorized users can plug their machine into a public terminal and
-gain access to the network. Security has been put in place such as
-WEP, but this security can be subverted with tools like !AirSnort.
-One approach to solving these problems is to not rely on the
-wireless security features , and instead to place an authentication
-gateway in front of the wireless network or public access area and
-force users to authenticate against it before using the
-network. This HOWTO describes how to set up this gateway with Linux.
-
-
-----
-!!1.1. Copyright Information
-
- This document is copyrighted (c) 2001 Nathan Zorn. Permission is
-granted to copy, distribute and/or modify this document under the
-terms of the GNU Free Documentation License, Version 1.1 or any
-later version published by the Free Software Foundation; with no
-Invariant Sections, with no Front-Cover Texts, and with no
-Back-Cover Texts. A copy of the license is available at
-http://www.gnu.org/copyleft/fdl.html
-
-
-
-
- If you have any questions, please contact
-`zornnh@musc.edub
-
-
-----
-!!1.2. Disclaimer
-
- No liability for the contents of this documents can be accepted.
-Use the concepts, examples and other content at your own risk. As
-this is a new edition of this document, there may be errors and
-inaccuracies, that may of course be damaging to your system.
-Proceed with caution, and although this is highly unlikely, the
-author(s) do not take any responsibility for that.
-
-
-
-
- All copyrights are held by their by their respective owners,
-unless specifically noted otherwise. Use of a term in this
-document should not be regarded as affecting the validity of any
-trademark or service mark.
-
-
-
-
- Naming of particular products or brands should not be seen as
-endorsements.
-
-
-
-
-
-You are strongly recommended to take a backup of your system
-before major installation and backups at regular intervals.
-
-
-----
-!!1.3. New Versions
-
-
-The newest release of this document can be found at
- http://www.itlab.musc.edu/~nathan/authentication_gateway/
-.
-Related HOWTOs can be found at the
- Linux Documentation Project homepage.
-
-
-----
-!!1.4. Credits
-
-Jamin W. Collins
-
-
-
-Kristin E Thomas
-
-
-
-Logu
-
-----
-!!1.5. Feedback
-
-
-Feedback is most certainly welcome for this document. Without your
-submissions and input, this document wouldn't exist. Please send
-your additions, comments and criticisms to the following email
-address : `zornnh@musc.edub.
-
-
-----
-!!!2. What is needed
-
- This section describes what is needed for the authentication gateway.
-
-
-----
-!!2.1. Netfilter
-
- The authentication gateway uses Netfilter and iptables to manage the
-firewall. Please see the
- Netfilter HOWTO
-.
-
-
-----
-!!2.2. Software for dynamic Netfilter rules.
-
-
-One means to insert and remove Netfilter rules is to use
-pam_iptables. This is a pluggable authentication module (PAM)
-written by Nathan Zorn that can be found at
- http://www.itlab.musc.edu/~nathan/pam_iptables
-.
-This PAM module allows users to use ssh and telnet to authenticate
-to the gateway.
-
-
-
-
-
-Another means to dynamically remove and create Netfilter rules is
-to use !NocatAuth. !NocatAuth can be found at
- http://nocat.net
-.
-!NocatAuth provides a web client for authenticating to the gateway.
-
-
-----
-!!2.3. DHCP Server
-
- The authentication gateway will act as the dynamic host
-configuration protocol (DHCP) server for the public network. It
-only serves those requesting DHCP services on the public
-network. I used the
- ISC DHCP Server
-.
-
-
-----
-!!2.4. Authentication mechanism
-
-
-The gateway can use any means of PAM authentication. The
-authentication mechanism the Medical University of South Carolina
-uses is LDAP. Since LDAP was used for authentication, the pam
-modules on the gateway box were set up to use LDAP. More
-information can be found at
- http://www.padl.com/pam_ldap.html
-.
-PAM allows you to use many means of authentication. Please see the
-documentation for the PAM module you would like to use. For more
-information on other methods, see
- pam modules
-.
-
-
-
-
-
-If !NocatAuth is used, an authentication service needs to be setup.
-The !NocatAuth authentication service supports authentication with
-LDAP,RADIUS,MySQL,and a password file. More information can be
-found at
- http://nocat.net/download/!NoCatAuth/
-.
-
-
-----
-!!2.5. DNS Server
-
-
-The gateway box also serves as a DNS server for the public
-network. I installed Bind, and set it
-up as a caching nameserver. The rpm package caching-namserver was
-also used. This package came with Red Hat.
-
-
-----
-!!!3. Setting up the Gateway Services
-
-
-This section describes how to setup each piece of the
-authentication gateway. The examples used are for a public network
-in the 10..1.0 subnet. eth0 is the interface on the box that is
-connected to the internal network. eth1 is the interface connected
-to the public network. The IP address used for this interface is
-10..1.1. These settings can be changed to fit the network you are
-using. Red Hat 7.1 was used for the gateway box, so a lot of the
-examples are specific to Red Hat.
-
-
-----
-!!3.1. Netfilter Setup
-
- To setup netfilter the kernel must be recompiled to include
-netfilter support. Please see the Kernel-HOWTO
-for more information on configuring and compiling your kernel.
-
-
-
-
- This is what my kernel configuration looked like.
-
- #
-# Networking options
-#
-CONFIG_PACKET=y
-# CONFIG_PACKET_MMAP is not set
-# CONFIG_NETLINK is not set
-CONFIG_NETFILTER=y
-CONFIG_NETFILTER_DEBUG=y
-CONFIG_FILTER=y
-CONFIG_UNIX=y
-CONFIG_INET=y
-CONFIG_IP_MULTICAST=y
-# CONFIG_IP_ADVANCED_ROUTER is not set
-# CONFIG_IP_PNP is not set
-# CONFIG_NET_IPIP is not set
-# CONFIG_NET_IPGRE is not set
-# CONFIG_IP_MROUTE is not set
-# CONFIG_INET_ECN is not set
-# CONFIG_SYN_COOKIES is not set
-# IP: Netfilter Configuration
-#
-CONFIG_IP_NF_CONNTRACK=y
-CONFIG_IP_NF_FTP=y
-CONFIG_IP_NF_IPTABLES=y
-CONFIG_IP_NF_MATCH_LIMIT=y
-CONFIG_IP_NF_MATCH_MAC=y
-CONFIG_IP_NF_MATCH_MARK=y
-CONFIG_IP_NF_MATCH_MULTIPORT=y
-CONFIG_IP_NF_MATCH_TOS=y
-CONFIG_IP_NF_MATCH_TCPMSS=y
-CONFIG_IP_NF_MATCH_STATE=y
-CONFIG_IP_NF_MATCH_UNCLEAN=y
-CONFIG_IP_NF_MATCH_OWNER=y
-CONFIG_IP_NF_FILTER=y
-CONFIG_IP_NF_TARGET_REJECT=y
-CONFIG_IP_NF_TARGET_MIRROR=y
-CONFIG_IP_NF_NAT=y
-CONFIG_IP_NF_NAT_NEEDED=y
-CONFIG_IP_NF_TARGET_MASQUERADE=y
-CONFIG_IP_NF_TARGET_REDIRECT=y
-CONFIG_IP_NF_NAT_FTP=y
-CONFIG_IP_NF_MANGLE=y
-CONFIG_IP_NF_TARGET_TOS=y
-CONFIG_IP_NF_TARGET_MARK=y
-CONFIG_IP_NF_TARGET_LOG=y
-CONFIG_IP_NF_TARGET_TCPMSS=y
-
-
-
-
-
- Once netfilter has been configured, turn on IP forwarding by
-executing this command.
-
-
-
- echo 1 b /proc/sys/net/ipv4/ip_forward
-
-
- To make sure ip forwarding is enabled when the machine restarts
-add the following line to /etc/sysctl.conf.
-
-
-
- net.ipv4.ip_forward = 1
-
-
-
-If !NocatAuth is being used, you can skip to the !NoCatAuth gateway setup section.
-
-
-
-
-
-iptables needs to be installed. To install iptables either use a
-package from your distribution or install from source. Once the
-above options were compiled in the new kernel and iptables was
-installed, I set the following default firewall rules.
-
-
-
- iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE
-iptables -A INPUT -i eth0 -m state --state NEW, INVALID -j DROP
-iptables -A FORWARD -i eth0 -m state --state NEW, INVALID -j DROP
-iptables -I FORWARD -o eth0 -j DROP
-iptables -I FORWARD -s 10..1./24 -d 10..1.1 -j ACCEPT
-
-
- The above commands can also be put in an initscript to start up
-when the server restarts. To make sure the rules have been added
-issue the following commands:
-
-
-
- iptables -v -t nat -L
-iptables -v -t filter -L
-
-
- To save these rules I used Red Hat's init scripts.
-
-
-
- /etc/init.d/iptables save
-/etc/init.d/iptables restart
-
-
-
-Now the gateway box will be able to do network address translation
-(NAT), but it will drop all forwarding packets except those coming
-from within the public network and bound for the gateway.
-
-
-----
-!!3.2. Dynamic Netfilter rules.
-
-
-This section describes how to setup the software needed to
-dynamically insert and remove Netfilter rules on the gateway.
-
-
-----
-!3.2.1. PAM iptables Module
-
- The PAM session module that inserts the firewall rules is
-needed to allow forwarding for the authenticated client. To set it
-up simply get the source
-and compile it by running the following commands.
-
-
-
- gcc -fPIC -c pam_iptables.c
-ld -x --shared -o pam_iptables.so pam_iptables.o
-
-
- You should now have two binaries called
-pam_iptables.so and pam_iptables.o.
-Copy pam_iptables.so to
-/lib/security/pam_iptables.so.
-
-
-
- cp pam_iptables.so /lib/security/pam_iptables.so
-
-
- Now install the firewall script to /usr/local/auth-gw.
-
-
-
- mkdir /usr/local/auth-gw
-cp insFwall /usr/local/auth-gw
-
-
- The chosen authentication client for the gateway was ssh so we added the
-following line to /etc/pam.d/sshd.
-
-
-
- session required /lib/security/pam_iptables.so
-
-
- Now, when a user logs in with ssh, the firewall rule will be added.
-
-
-
-
- To test if the pam_iptables module is working perform the following
-steps:
-
-
-
-
-
-
-
-#
-
-Log into the box with ssh.
-
-
-#
-#
-
-Check to see if the rule was added with the command
-__iptables -L -v__.
-
-
-#
-#
-
-Log out of the box to make sure the rule is removed.
-
-
-#----
-!3.2.2. !!!NoCatAuth gateway
-
-
-This section describes the process of setting up the !!NocatAuth
-gateway. To setup !!NocatAuth get the source and
-install with the following steps.
-
-
-
-
-
-Make sure gpgv is installed. gpgv is a PGP signature verifier.
-It is part of gnupg and can be found at http://www.gnupg.org/download.html.
-
-
-
-
- Unpack the !!NocatAuth tar file.
-
- tar xvzf !!NocatAuth-x.xx.tar.gz
-
-
-
-
-
-
-If you do not want !!NoCatAuth to be in the directory
-/usr/local/nocat, edit the Makefile and change INST_PATH to the
-directory you would like !!NoCatAuth to reside.
-
-
-
-
- Next build the gateway.
-
- cd !NoCatAuth-x.xx
-make gateway
-
-
-
-
-
-
-Edit the /usr/local/nocat.conf file. Please see the INSTALL
-documentation for details on what is required in the conf
-file. An example conf file looks like the following:
-
-
-
-
- ###### gateway.conf -- !NoCatAuth Gateway Configuration.
- #
- # Format of this file is: Directive Value, one per
- # line. Trailing and leading whitespace is ignored. Any
- # line beginning with a punctuation character is assumed to
- # be a comment.
- Verbosity 10
- #we are behind a NAT so put the gateway in passive mode
- !!GatewayMode Passive
- !!GatewayLog /usr/local/nocat/nocat.log
- !!LoginTimeout 300
- ######Open Portal settings.
- !!HomePage http://www.itlab.musc.edu/
- !!DocumentRoot /usr/local/nocat/htdocs
- !!SplashForm splash.html
- ###### Active/Passive Portal settings.
- !!TrustedGroups Any
- !!AuthServiceAddr egon.itlab.musc.edu
- AuthServiceURL https://$!AuthServiceAddr/cgi-bin/login
- !LogoutURL https://$!AuthServiceAddr/forms/logout.html
- ###### Other Common Gateway Options.
- !!AllowedWebHosts egon.itlab.musc.edu
- !!ResetCmd initialize.fw
- !!PermitCmd access.fw permit $MAC $IP $Class
- !!DenyCmd access.fw deny $MAC $IP $Class
-
-
-
-Now you should be able to start the gateway. If any problems
-occur, please see the INSTALL documentation in the unpacked
-!NoCatAuth directory. The following command will start the
-gateway:
-
- /usr/local/nocat/bin/gateway
-
-
-
-----
-!!3.3. DHCP Server Setup
-
-I installed DHCP using the following
-dhcpd.conf file.
-
-
-
- subnet 10..1.0 netmask 255.255.255.0 {
-# --- default gateway
-option routers 10..1.1;
-option subnet-mask 255.255.255.;
-option broadcast-address 10..1.255;
-option domain-name-servers 10..1.1;
-range 10..1.3 10..1.254;
-option time-offset -5; # Eastern Standard Time
-default-lease-time 21600;
-max-lease-time 43200;
-}
-
-
- The server was then run using eth1 , the interface to the public
-net.
-
-
-
- /usr/sbin/dhcpd eth1
-----
-!!3.4. Authentication Method Setup
-
-
-Authentication with PAM and a !NoCatAuth authentication service is
-described. Both examples are done with LDAP. Other means of
-authentication besides LDAP can be used. Please read the
-documentation for PAM and !NoCatAuth to find the steps to use
-another authentication source.
-
-
-----
-!3.4.1. PAM LDAP
-
- As indicated in previous sections, I've set this gateway up to use
-LDAP for authenticating. However, you can use any means that PAM
-allows for authentication. See Section 2.4 for
-more information.
-
-
-
-
-
-In order to get PAM LDAP to authenticate, I installed OpenLDAP and configured it
-with the following in /etc/ldap.conf.
-
-
-
- # Your LDAP server. Must be resolvable without using LDAP.
-host itc.musc.edu
-# The distinguished name of the search base.
-base dc=musc,dc=edu
-ssl no
-
-
-
-The following files were used to configure PAM to do the LDAP
-authentication. These files were generated by Red Hat's
-configuration utility.
-
-
-
-
-
-
-; /etc/pam.d/system-auth was created and looked
-like this.:
-
-
- #%PAM-1.
-# This file is auto-generated.
-# User changes will be destroyed the next time authconfig is run.
-auth required /lib/security/pam_env.so
-auth sufficient /lib/security/pam_unix.so likeauth nullok
-auth sufficient /lib/security/pam_ldap.so use_first_pass
-auth required /lib/security/pam_deny.so
-account required /lib/security/pam_unix.so
-account
[[default=ok user_unknown=ignore service_err=ignore system_err=ignore
] /lib/security/pam_ldap.so
-password required /lib/security/pam_cracklib.so retry=3
-password sufficient /lib/security/pam_unix.so nullok use_authtok
-password sufficient /lib/security/pam_ldap.so use_authtok
-password required /lib/security/pam_deny.so
-session required /lib/security/pam_limits.so
-session required /lib/security/pam_unix.so
-session optional /lib/security/pam_ldap.so
-
-
-
-; Then the following
-/etc/pam.d/sshd file was created.:
-
-
- #%PAM-1.
-auth required /lib/security/pam_stack.so service=system-auth
-auth required /lib/security/pam_nologin.so
-account required /lib/security/pam_stack.so service=system-auth
-password required /lib/security/pam_stack.so service=system-auth
-session required /lib/security/pam_stack.so service=system-auth
-#this line is added for firewall rule insertion upon login
-session required /lib/security/pam_iptables.so debug
-session optional /lib/security/pam_console.so
-
-
-
-----
-!3.4.2. !NoCatAuth Service
-
-
-It is recommended to install the !NoCatAuth Service on another
-server besides the gateway. A seperate server was used in my
-examples. In order to setup a !NoCatAuth Service, you will need
-the following software:
-
-
-
-
-
-
-
-#
-
-
-An SSL enabled webserver, preferably with a registered SSL cert.
-I used Apache + mod_ssl.
-
-
-
-#
-#
-
- Perl 5 (5.6 or better recommended)
-
-
-
-#
-#
-
-
-Net::LDAP, Digest::MD5, DBI, and DBD::MySQL perl modules (get them
-from CPAN) The module you need depends on what authentication
-source you are going to use. In my example Net::LDAP is used as
-the authentication means.
-
-
-
-#
-#
-
- Gnu Privacy Guard (gnupg 1..6 or better), available at
-http://www.gnupg.org/download.html
-
-
-
-#
-
- To install unpack the tar file.
-
- $ tar zvxf !NoCatAuth-x.xx.tar.gz
-
-
-
-
-
- If you would like to change the path that !NoCatAuth resides , edit the
-Makefile and change INST_PATH to the desired directory.
-
-
-
-
- Next run the command:
-__ make authserv __
-This installs everything in /usr/local/nocat or what you changed INST_PATH
-to.
-
-
-
-
- Then run __ make pgpkey __
-The defaults should be fine for most purposes.
-IMPORTANT: do NOT enter a passphrase! Otherwise, you will get strange
-messages when the auth service attempts to encrypt messages, and tries to
-read your passphrase from a non-existent tty
-
-
-
-
- Edit /usr/local/nocat/nocat.conf to fit your situation.
-Here is an example:
-
- ###### authserv.conf -- !NoCatAuth Authentication Service Configuration.
- #
- # Format of this file is: Directive Value, one per
- # line. Trailing and leading whitespace is ignored. Any
- # line beginning with a punctuation character is assumed to
- # be a comment.
- !Verbosity 10
- !!HomePage http://www.itlab.musc.edu/
- !!DocumentRoot /usr/local/nocat/htdocs
- # LDAP source
- !!DataSource LDAP
- !LDAPHost authldap.musc.edu
- !LDAPBase dc=musc,dc=edu
- !!UserTable Member
- !UserIDField User
- !!UserPasswdField Pass
- !!UserAuthField Status
- !!UserStampField Created
- !!GroupTable Network
- !GroupIDField Network
- !!GroupAdminField Admin
- !!MinPasswdLength 8
- # !LocalGateway -- If you run auth service on the same subnet
- # (or host) as the gateway you need to specify the hostname
- # of the gateway. Otherwise omit it. (Requires Net::Netmask)
- #
- # !LocalGateway 192.168.1.7
- !!LoginForm login.html
- !LoginOKForm login_ok.html
- !!FatalForm fatal.html
- !!ExpiredForm expired.html
- !!RenewForm renew.html
- !!PassiveRenewForm renew_pasv.html
- !!RegisterForm register.html
- !RegisterOKForm register_ok.html
- !!RegisterFields Name URL Description
- !!UpdateForm update.html
- !!UpdateFields URL Description
- ###### Auth service user messages. Should be self-explanatory.
- #
- !!LoginGreeting Greetings! Welcome to the Medical University of SC's Network.
- !!LoginMissing Please fill in all fields!
- !!LoginBadUser That e-mail address is unknown. Please try again.
- !!LoginBadPass That e-mail and password do not match. Please try again.
- !!LoginBadStatus Sorry, you are not a registered co-op member.
- !!RegisterGreeting Welcome! Please enter the following information to register.!RegisterMissing Name, E-mail, and password fields must be filled in.
- !!RegisterUserExists Sorry, that e-mail address is already taken. Are you already registered?
- !!RegisterBadUser The e-mail address provided appears to be invalid. Did you spell it correctly?
- !!RegisterInvalidPass All passwords must be at least six characters long.
- !!RegisterPassNoMatch The passwords you provided do not match. Please try again.
- !!RegisterSuccess Congratulations, you have successfully registered.
- !!UpdateGreeting Enter your E-mail and password to update your info.
- !!UpdateBadUser That e-mail address is unknown. Please try again.
- !!UpdateBadPass That e-mail and password do not match. Please try again.
- !!UpdateInvalidPass New passwords must be at least eight characters long.
- !!UpdatePassNoMatch The new passwords you provided do not match. Please try again.
- !!UpdateSuccess Congratulations, you have successfully updated your account.
-
-
-
-
-
- Make sure /usr/local/nocat/pgp is owned by the web server user. (ie..nobody or www-data)
-
-
-
-
- Add etc/authserv.conf to your apache httpd.conf file.
-
- Include /usr/local/nocat/etc/authserv.conf
-
-
-
-
- Copy your /usr/local/nocat/trustedkeys.pgp to the gateway.
-Restart apache and try it out. Please see the !NoCatAuth
-documentation for more information. It can be found in docs/ in
-the unpacked !NoCatAuth directory.
-
-
-----
-!!3.5. DNS Setup
-
- I installed the default version of Bind that comes with Red Hat
-7.1, and the caching-nameserver RPM. The DHCP server tells the
-machines on the public net to use the gateway box as their
-nameserver.
-
-
-----
-!!!4. Using the authentication gateway
-
-
-To use the authentication gateway, configure your client machine to
-use DHCP. Install a ssh client on the box and ssh into the gateway.
-Once you are logged in, you will have access to the internal network.
-The following is an example session from a unix based client:
-
-
-
- bashbssh zornnh@10..1.1
- zornnh's Password:
- gatewayb
-
-
- As long as you stayed logged in, you will have access. Once you log
-out, access will be taken away.
-
- To use the authentication gateway with !!NoCatAuth installed, configure
-your client machine to use DHCP. Install a web browser such as
-Mozilla. Start up the web browser. The browser should be redirected
-to the authentication screen. Submit your username and password and a
-screen will pop up explaining that you are authenticated to the
-network and to keep the window open to remain authenticated. Click
-logout or close the window to end the session.
-
-
-----
-!!!5. Concluding Remarks
-
-
-
-
-* This method of security does not rely on the security provided by the wireless network community. It assumes that the entire wireless network is insecure and outside of your network.
-
-* The gateway does not encrypt traffic. It only allows you access to the network behind it. If encryption and authentication are desired, a VPN should be used.
-
-----
-!!!6. Additional Resources
-
-* A document describing the NASA implementation of the authentication gateway.
-
-
-
-* A white paper describing how the University of Alberta created an authentication gateway.
-
-
-
-* Nocat.net has an authentication gateway for wireless networks. This software
-has a web based client.
-
-
-
-* Horatio: Authenticated Network Access is a firewall authentication tool. The premise: Legitimate users want to attach laptops and other mobile hosts to the network, but security demands that illegitimate users be prevented from accessing the internal, secure network and from abusing the general Internet.
-
-
-
-----
-!!!7. Questions and Answers
-
- This is just a collection of what I believe are the most common
-questions people might have. Give me more feedback and I will turn
-this section into a proper FAQ.
-
-
-# Why are the iptables rules not flushing out when a client closes the telnet window? It works if the client logsout of the telnet session. In case of ssh the rules get flushed even if the ssh window is closed.
-
-I have not come up with a good answer or solution to this problem. Logu has contributed some modifications to pam_iptables and a set of other tools to solve this problem. These tools can be found in the contrib directory with pam_iptables
.
+Describe
[HowToAuthenticationGatewayHOWTO
] here
.
